It is important to reduce the amount of power consumed by display devices, that is, provide display devices that save power. An example of one type of display device is liquid crystal display (LCD) devices. Until now, efforts have been made to improve LCDs themselves. For example, light-emitting diodes (LEDs) have been adopted in place of cold-cathode fluorescent lamps (CFLs), the power consumed by LCD backlighting devices has been reduced by adopting power-saving semiconductors in the circuitry, drive methods have been improved by dynamically changing backlighting when black is displayed, and materials have been improved, for example, by the development of liquid crystal elements that change at low voltage.